Security bit for designating the security status of information

Details Security bit for designating the security status of information Security bit for designating the security status of information

1982-06-30

1986-05-20

Shaw, Gareth D.

Boots, shoes, and leggings

G06F 1214

Patent

active

045905525

ABSTRACT:
A digital processing device implemented on a single semiconductor substrate includes an nonvolatile memory for the storage of data and instructions that define operations on the data. The memory is connected to an inhibit logic interface which is in turn connected to an information bus. The information bus is connected to a central processor that performs the operations on data. An external interface is also connected to the information bus to provide information on the information bus to external devices. At least one security bit is provided for designating security status of information stored in the memory. Address logic is connected to the information bus to determine when information is being accessed from the memory. Security control circuitry is also provided and is connected to the central processing unit, the address logic, to determine when an instruction is being fetched by the central processing unit and if the instruction is being fetched from the memory. The security control circuitry is connected to the inhibit logic interface to inhibit the information bus interface to the memory during selected operations in the central processing unit.

REFERENCES:
patent: 3742458 (1973-06-01), Inoue et al.
patent: 3827029 (1974-07-01), Schlotterer et al.
patent: 4093987 (1978-06-01), Gaudette et al.
patent: 4135240 (1979-01-01), Ritchie
patent: 4168396 (1979-09-01), Best
patent: 4177510 (1979-12-01), Appel
patent: 4278837 (1981-07-01), Best
patent: 4319079 (1982-03-01), Best
patent: 4430709 (1984-02-01), Schleupen
patent: 4434464 (1984-02-01), Suzuki et al.

Affiliated with

Also associated with

Rating

Security bit for designating the security status of information does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Security bit for designating the security status of information , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Security bit for designating the security status of information will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2112380